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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 298: 122798, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37172420

RESUMO

The use of sensor fusion, a novel method of combining artificial senses, has become increasingly popular in the assessment of food quality. This study employed a combination of the colorimetric sensor array (CSA) and mobile near-infrared (NIR) spectroscopy to predict free fatty acids in wheat flour. In conjunction with a partial least squares model, Low- and mid-level fusion strategies were used for quantification. Accordingly, performance of the built model was evaluated based on higher correlation coefficients between calibration and prediction (RC and RP), lower root mean square error of prediction (RMSEP), and a higher residual predictive deviation (RPD). The mid-level fusion coupled PLS model produced superior data fusion findings, with RC = 0.8793, RMSECV = 7.91 mg/100 g, RP = 0.8747, RMSEP = 6.99 mg/100 g, and RPD = 2.27. The findings of the study suggest that the NIR-CSA fusion approach could be effectively applied to the prediction of free fatty acids in wheat flour.


Assuntos
Ácidos Graxos não Esterificados , Triticum , Colorimetria , Quimiometria , Farinha , Análise dos Mínimos Quadrados
2.
Carbohydr Polym ; 235: 115944, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122483

RESUMO

Carboxymethyl cellulose (CMC) based novel functional films containing Chinese chives root extract (CRE) at different concentrations (1, 3 and 5 % in w/w) were successfully fabricated. It was revealed by SEM that higher extract concentration triggered the formation of agglomerates within the film. Tensile strength of the films was decreased from 30.91 to 16.48 MPa. Thickness of films was increased from 43 to 84 µm, while decrease in water solubility from 77.51-52.91 %, swelling degree from 55.74 to 40.37 %, and water vapor permeability from 5.76 to 1.17 10-10 gm-1s-1 Pa-1 was observed. DPPH and ABTS radical scavenging ability of CMC-CRE films was increased from 0 to 58 % and 82 %, respectively. CMC-CRE5 film showed the highest biodegradability of 58.14 %. The film prepared by the addition of CRE into CMC also exhibited good antioxidant and antimicrobial activity indicating that it could be developed as a bio-composite food packaging material for the food industry.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Carboximetilcelulose Sódica/farmacologia , Cebolinha-Francesa/química , Embalagem de Alimentos , Antibacterianos/química , Antioxidantes/química , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Carboximetilcelulose Sódica/química , China , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Picratos/antagonistas & inibidores , Solubilidade , Vapor , Ácidos Sulfônicos/antagonistas & inibidores , Propriedades de Superfície
3.
Int J Biol Macromol ; 150: 595-604, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057859

RESUMO

The objective of the present study was to develop chitosan (CS) based novel functional films containing Chinese chive root extract (CRE) using solution casting method. CRE at different concentrations (1, 3 and 5% in w/w) were incorporated into the film-forming solution. Scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermal behavior analysis (DSC & TGA) were performed to investigate the structure, potential interaction and thermal stability of prepared films. It was revealed by SEM that higher extract concentration triggered the formation of agglomerates within the films. Incorporation of CRE into CS resulted in decrease tensile properties of the films from 28.9 to 15.4 MPa, whereas thickness was increased from 0.076 to 0.113 mm. The water solubility, swelling degree and water vapor permeability were significantly decreased from 31.6 to 18.7%, 57.4 to 40.5% and 15.67 to 7.81 × 10-11 g·m-1s-1Pa-1, respectively. DPPH and ABTS radical scavenging ability of CS-CRE films were increased from 6.95 to 47.05% and 11.98 to 57.38%, respectively. CS-CRE5 film showed the highest biodegradability of 47.36%. The films prepared by addition of CRE into CS exhibited good antioxidant and antimicrobial activity indicating that it could be developed as bio-composite food packaging material for food industry.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Cebolinha-Francesa/química , Embalagem de Alimentos , Extratos Vegetais/química , Raízes de Plantas/química , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Fenômenos Mecânicos , Compostos Fitoquímicos/química , Polifenóis/química , Análise Espectral
4.
Int J Biol Macromol ; 114: 547-555, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29578019

RESUMO

In the present study, apple peel polyphenols (APP) were incorporated into chitosan (CS) to develop a novel functional film. Scanning electron microscopy, Fourier transform-infrared spectroscopy and thermogravimetric analyses were performed to study the structure, potential interaction and thermal stability of the prepared films. Physical properties including moisture content, density, color, opacity, water solubility, swelling ration and water vapor permeability were measured. The results revealed that addition of APP into CS significantly improved the physical properties of the film by increasing its thickness, density, solubility, opacity and swelling ratio whereas moisture content and water vapor permeability were decreased. Tensile strength and elongation at break of the CS-APP film with 1% APP was 16.48MPa and 13.33%, respectively, significantly lower than those for CS control film. Thermal stability of the prepared films was decreased while antioxidant and antimicrobial activities of the CS-based APP film were significantly increased. CS-APP film with 0.50% APP concentration exhibited good mechanical and antimicrobial properties, indicating that it could be developed as bio-composite food packaging material for the food industry.


Assuntos
Anti-Infecciosos , Quitosana/química , Embalagem de Alimentos , Frutas/química , Malus/química , Membranas Artificiais , Polifenóis , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Polifenóis/química , Polifenóis/isolamento & purificação
5.
Int J Food Sci Nutr ; 65(1): 28-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24112293

RESUMO

This study was conducted to evaluate the combined effects of blanching and sonication on carrot juice quality. Carrots were blanched at 100 °C for 4 min in normal and acidified water. Juice was extracted and sonicated at 15 °C for 2 min keeping pulse duration 5 s on and 5 s off (70% amplitude level and 20 kHz frequency). No significant effect of blanching and sonication was observed on Brix, pH and titratable acidity except acidified blanching that decreased pH and increased acidity significantly. Peroxidase was inactivated after blanching that also significantly decreased total phenol, flavonoids, tannins, free radical scavenging activity, antioxidant capacity and ascorbic acid and increased cloud and color values. Sonication could improve all these parameters significantly. The present results suggest that combination of blanching and sonication may be employed in food industry to produce high-quality carrot juice with reduced enzyme activity and improved nutrition.


Assuntos
Bebidas/análise , Daucus carota/química , Manipulação de Alimentos , Qualidade dos Alimentos , Raízes de Plantas/química , Antioxidantes/análise , Ácido Ascórbico/análise , China , Culinária , Daucus carota/enzimologia , Estabilidade Enzimática , Flavonoides/análise , Humanos , Concentração de Íons de Hidrogênio , Valor Nutritivo , Peroxidase/química , Peroxidase/metabolismo , Fenóis/análise , Pigmentação , Proteínas de Vegetais Comestíveis/química , Proteínas de Vegetais Comestíveis/metabolismo , Raízes de Plantas/enzimologia , Sonicação/efeitos adversos , Taninos/análise
6.
Ultrason Sonochem ; 21(1): 93-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23835397

RESUMO

A study was initiated with the objective of evaluating the effects of sonication treatment on quality characteristics of apple juice such as polyphenolic compounds (chlorogenic acid, caffeic acid, catechin, epicatechin and phloridzin), sugars (fructose, glucose and sucrose), mineral elements (Na, K, Ca, P, Mg, Cu and Zn), total carotenoids, total anthocyanins, viscosity and electrical conductivity. The fresh apple juice samples were sonicated for 0, 30 and 60 min at 20 °C (frequency 25 kHz and amplitude 70%), respectively. As results, the contents of polyphenolic compounds and sugars significantly increased (P<0.05) but the increases were more pronounced in juice samples sonicated for 30 min whereas, total carotenoids, mineral elements (Na, K and Ca) and viscosity significantly increased (P<0.05) in samples treated for 60 min sonication. Losses of some mineral elements (P, Mg and Cu) also occurred. Total anthocyanins, Zn and electrical conductivity did not undergo any change in the sonicated samples. Findings of the present study suggest that sonication technique may be applied to improve phytonutrients present naturally in apple juice.


Assuntos
Carboidratos/análise , Carotenoides/análise , Manipulação de Alimentos/métodos , Malus/química , Minerais/análise , Polifenóis/análise , Sonicação , Antocianinas/análise , Bebidas , Condutividade Elétrica , Viscosidade
7.
Ultrason Sonochem ; 21(3): 984-90, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24373787

RESUMO

Enzymatic browning and microbial growth lead to quality losses in apple products. In the present study, fresh apple juice was thermosonicated using ultrasound in-bath (25 kHz, 30 min, 0.06 W cm(-3)) and ultrasound with-probe sonicator (20 kHz, 5 and 10 min, 0.30 W cm(-3)) at 20, 40 and 60°C for inactivation of enzymes (polyphenolase, peroxidase and pectinmethylesterase) and microflora (total plate count, yeast and mold). Additionally, ascorbic acid, total phenolics, flavonoids, flavonols, pH, titratable acidity, (°)Brix and color values influenced by thermosonication were investigated. The highest inactivation of enzymes was obtained in ultrasound with-probe at 60°C for 10 min, and the microbial population was completely inactivated at 60°C. The retention of ascorbic acid, total phenolics, flavonoids and flavonols were significantly higher in ultrasound with-probe than ultrasound in-bath at 60°C. These results indicated the usefulness of thermosonication for apple juice processing at low temperature, for enhanced inactivation of enzymes and microorganisms.


Assuntos
Bebidas , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Temperatura Alta , Malus , Sonicação , Ácido Ascórbico/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Catecol Oxidase/metabolismo , Malus/enzimologia , Peroxidases/metabolismo
8.
Ultrason Sonochem ; 20(5): 1182-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23522904

RESUMO

Fresh apple juice treated with ultrasound (for 0, 30, 60 and 90 min, at 20 °C, 25 kHz frequency) was evaluated for different physico-chemical, Hunter color values, cloud value, antioxidant capacity, scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical, ascorbic acid, total phenolics, flavonoids, flavonols and microbial characteristics. No significant effect of sonication was observed on pH, total soluble solids (°Brix) and titratable acidity of apple juice. Sonication significantly improved ascorbic acid, cloud value, phenolic compounds, antioxidant capacity, DPPH free radical scavenging activity and differences in Hunter color values. Moreover, significant reduction in microbial population was observed. Findings of the present study suggested that sonication treatment could improve the quality of apple juice. It may successfully be employed for the processing of apple juice with improved quality and safety from consumer's health point of view.


Assuntos
Bebidas/normas , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Malus , Sonicação , Bebidas/microbiologia , Manipulação de Alimentos/normas , Malus/química , Malus/microbiologia
9.
Phytochemistry ; 72(6): 458-64, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21353685

RESUMO

A milk coagulating protease was purified ∼10.2-fold to apparent homogeneity from ginger rhizomes in 34.9% recovery using ammonium sulfate fractionation, together with ion exchange and size exclusion chromatographic techniques. The molecular mass of the purified protease was estimated to be ∼36kDa by SDS-PAGE, and exhibited a pI of 4.3. It is a glycoprotein with 3% carbohydrate content. The purified enzyme showed maximum activity at pH 5.5 and at a temperature of ∼60°C. Its protease activity was strongly inhibited by iodoacetamide, E-64, PCMB, Hg(2+) and Cu(2+). Inhibition studies and N-terminal sequence classified the enzyme as a member of the cysteine proteases. The cleavage capability of the isolated enzyme was higher for α(s)-casein followed by ß- and κ-casein. The purified enzyme differed in molecular mass, pI, carbohydrate content, and N-terminal sequence from previously reported ginger proteases. These results indicate that the purified protease may have potential application as a rennet substitute in the dairy industry.


Assuntos
Cisteína Endopeptidases/metabolismo , Leite/metabolismo , Rizoma/enzimologia , Zingiber officinale/enzimologia , Animais , Cisteína Endopeptidases/química , Cisteína Endopeptidases/isolamento & purificação , Concentração de Íons de Hidrogênio , Leite/química , Temperatura
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